Natural stones such as granite or marble have been used for interior building materials due to their beautiful surface patterns. Recently, natural stone has been spotlighted as a material having a high quality texture, such that demand for natural stone has significantly increased for use as a flooring material, a wall material, a sink top plate material, and the like.
Natural stone, however, has not been popularized due to disadvantages such as high cost, a heavy weight, weakness against impact in spite of a high surface hardness and beautiful patterns. Accordingly, various kinds of artificial stones have been developed.
Artificial stone may have various images and patterns unlike natural stone, may have an excellent gloss, and may be significantly resistant against extreme temperature change. In addition, since water absorption rate is low, and strength is high, artificial stone may provide an excellent interior effect in high-end houses, hotels, apartments, and the like, such that a demand for artificial stone has rapidly increased around the world.
In general, artificial stone can be classified into two types. One is a general artificial marble manufactured by adding various additives such as an inorganic filler, a coloring agent, a curing agent, and the like, to an acrylic resin or an unsaturated polyester-based resin. The other is a resin-based reinforced natural stone (also referred to as an engineered stone) manufactured by vibration-compression or vacuum vibration-compression molding a composition obtained by mixing an inorganic-based (silica-based) natural mineral and a binder resin to thereby have a texture of natural stone as it is.
The resin-based reinforced natural stone may be manufactured so as to have various colors and textures according to the kinds of mixed natural minerals, color of the binder resin and/or pigment, a stirring process, and the like. Since natural mineral is used as a raw material, the resin-based reinforced natural stone can have excellent natural textures as compared to general artificial marble, such that demand thereof has significantly increased.
The resin-based reinforced natural stone as described above may be manufactured so as to have a single color, manufactured so as to have multi-tones by adding different pigments, or manufactured so as to have a natural stone textile by using a chip.
However, most of the resin-based reinforced natural stones as described above have a two-dimensional pattern, a saturation thereof is not high, and interfaces thereof are not distinguished, such that it is difficult to have a stereoscopic texture. Occasionally, there is a natural stone having a particular and stereoscopic pattern, but this natural stone is scarce. Therefore, this natural stone has been traded at high cost in accordance with the scarcity.
A method of manufacturing a resin-based reinforced natural stone capable of simultaneously imparting a stereoscopic effect and a planar effect by polishing a surface of the resin-based reinforced natural stone step by step in order to conspicuously express the stereoscopic effect has been disclosed in Korean Patent Laid-Open Publication No. 2013-0010143.
However, since the stereoscopic effect of the resin-based reinforced natural stone itself is unnoticeable, there is a limitation in implementing a desired stereoscopic texture only by polishing the surface.
A method of manufacturing an engineered stone containing silica pretreated in order to improve whiteness of a resin-based reinforced natural stone itself has been disclosed Korean Patent Laid-Open Publication No. 2012-0064233. However, there is a limitation in that even though whiteness is improved, the stereoscopic texture is not improved.
Therefore, there is a need for a resin-based reinforced natural stone capable of exhibiting a natural stone texture by reflecting a stereoscopic effect of the resin-based reinforced natural stone itself without a complicated surface polishing process.